Coz you sounded as if you had ventured on a tap water check expedition all over Poland and examined the quality of water in a few dozen cities and towns and then published the results of your quest in Medical Journal. :)

One other very important issue related to this topic is air quality... This is a huge issue in Poland in the heating months (so Sept to May). Generally, the first thing that you ntice you when arriving in Poland from the West is the choking/smelly air - generally, the southern half of the country is much worse... Kraków and Śląsk are the worst. This is due to people heating their homes with very poor fuel (coal derivatives) and using old style furnaces, because gas and electricity are very expensive - even more expensive than in the West without compensating for the differences in income...

This is the next huge issue the country needs to address instead of pretending it is OK to do nothing. Estimates say between 30,000 to 50,000 people die each year due to the air pollution - so half a million a decade! Compare that to road fatalities of about 2,800/yr... ;-(((